Triple valve.



PATENTED'JAN. 9, 1906.

R. E. CHAPMAN. TRIPLE VALVE.

APPLICATION FILED SEPT.-20, 1904.

wigs UNITED STATES PATENT OFFICE.

' ROBERT E. CHAPMAN, OF COLORADO CITY, COLORADO.

TRIPLE VALVE.

Specification of Letters Patent.

Patented Jan. 9, 1906.

Application filed September 20, 1904:. serial No. 225,203.

, To all whom, it may concern.-

Be it known that 1, ROBERT E. CHAPMAN, a citizen of the United States, residing at Colorado City, in the county of El Paso, in the State of Colorado, have invented certain new and useful Improvements in Triple Valves, of which the following is a specificatriple valves now in general use.

My invention relates more particularly to the means for feeding or charging the auxiliary reservoir from the train-pipe, which according to my invention is done by a direct check valved connection between the reservoir and the usual drain-cup of the triple valve, with the result that the feedin air passes directly to the reservoir and not through the valve proper, so that dust, dirt, and scale accompanying or in suspension in the air finds its way into the reservoir where it does no special harm. The comparatively frequent and expensive cleaning and overhauling of the working parts of triple valves is thereby avoided.

- Again, my invention provides for the rapid charging and recharging of the auxiliary reservoir, thus enabling the engineer to have his train under full control at all times no matter how long or steep the grade may be, and thereby preventing runaway trains.

Other features of advantage and utility in my invention will be apparent or will be explained after the followin description of the construction and mode 0 operation.

In the drawing 'the single figure represents a central vertical section of a standard Westinghouse triple valve to which I have shown my invention applied.

The Westinghouse triple valve herein shown is of the well-known standard construction with the exception that the feedgroove in the bushing l of the piston 2 is dispensed with. In applyin my invention to old valves in service this feed-groove or bypass around the piston is closed or plugged up in suitable manner; but in new valves the bushing is left entirethat is, without the usual cut therein to form the groove.

As is well known, in the standard Westinghouse triple valve the auxiliary-reservoir feed is past the piston, through the slidevalve chamber, and past the slide-valve into the auxiliary reservoir 3, also here indicated by the letters A R. The parts here shown are those of a freight-car equipment, in which case the brake-cylinder connection from the triple valve is had through a pipe 4, passing longitudinally of and through the auxiliaryreservoir to the brake-cylinder, (not shown,) which is connected'to the outer end of the reservoir. In the present instance said feed past the piston 2 is entirely discontinued, and the feed is had directly from the train-line to the reservoir by means of a connection from the drain-cup 5 of the triple valve, which cup is sometimes designated as the check-valve" case and which is in diroot and immediate communication with the train-line. This feeding connection comprises in the present instance a right-angled pipe 6 at one end screwing into the triplevalve casing and having its other end also screw-threaded in order that it may be connected to another pipe 7, whose upper end screws into the auxiliary reservoir and communicates therewith. As shown, the connection between the pipes is made bya unionnut 8, which also serves to clamp between the ends of such pipe a guide 9 for the stem 10 of a check-valve 11. This check-valve seats by gravity upon a seat 12, formed in Y the pipe 6, with the result that under no conditions can the air-pressure flow back to the train-line. However, free passage of the airpressure is permitted in the opposite directionthat is, from the train-line to the auxiliary reservoir.

The check-valve is of the proper weight, so that the piston will be forced to normal or release position before the check-valve opens for feedingto the auxiliary reservoir. Assuming that the check-valve has a train-pipe exposure of one-fourth ofan inch and weighs two ounces, the resistance would be two pounds per square inch, so that with a piston area of nine inches there would be eighteen pounds resisting power on the trainline side of the piston, thus guaranteeing the restoration of the piston prior to the feeding operation.

The operation of my device will be understoodfrom the foregoing description, and it need only be stated that in the feeding oper ation'the check-valve is lifted, thereby opening the direct communication between the train-line and the auxiliary reservoir, and that in the operation of the brakes the checkvalve is seated and held thereto by its gravity assisted by the reservoirpressure.

Several of the advantages of my invention have already been stated, and in addition I will refer to some others. In case the triplevalve piston of the ordinary Westinghouse valve should stick after a train-line reduction the communication between the reservoir and the train pipe or line remains open, thereby permitting such pressure to flow to the train-line and to atmosphere. In a triple valve equipped with my improvements this cannot occur, as the pressure is absolutely cut off from the train-line after once entering the auxiliary reservoir. Again, in the terminal testing of triple valves the clogged condition of the charging-groove around the piston does not manifest itself, because the reservoir is already charged when the service test is made. After such first test is made the auxiliary reservoir is not fully charged or the charging takes a considerable time, both of which conditions are objectionable in practice. Such objections are avoided in triple valves equipped with my invention, inasmuch as the chargingpassage cannot clog. Moreover, it often occurs in actual practice that after a service application of the brake the graduating-valve is prevented by dirt from properly seating, with the result that the reservoir-pressure continues to reduce into the brake-cylinder until the train-line pressure is sufficient to force the slide-valve from lap to release position, so that the braking power of the particular triple valve is lost. It is obvious that this cannot occur in a valve provided with my invention.

I claim 1. The combination with an auxiliary reservoir of an air-brake system, of a triple valve having a pipe connection connected at its end with the triple valve and reservior and forming connection therebetween, a valve-stem guide separate from and arranged in said pipe connection, and a check-valve arranged in such connection and having a stem cooperating with such guide; substantially as described.

2. The combination, with a triple valve and the auxiliary reservoir 3, of a connection between the triple valve and reservoir comprising the pipes 6 and 7 joined by the unionnut 8 and communicating directly between the triple valve and reservoir, a check-valve guide arranged in one of the pipes and clamped therein by the union-nut 8, and a check-valve 11 within the pipe 6; substantially as described.

3. The combination, with an auxiliary reservoir, and with a triple valve having a draincup 5, of two pipes 6, 7 communicating between such cup and the reservoir, the sepa rate guide 9 in the pipe 6, and a check-valve 11 in such communication and guided by said guide; substantially as described.

ROBT. E. CHAPMAN.

Witnesses:

JOHN K. VANATTA, O. F. SPRINGER. 

